The use of vehicle-mounted post hole diggers is known in the prior art. More particularly, vehicle-mounted post hole diggers previously devised and utilized are known to consist basically of many seemingly-basic structural configurations, including a plurality of designs presenting the prior art which have been developed for the fulfillment of various objects and requirements dictated by the circumstances faced by the inventors. For example, U.S. Pat. No. 4,124,081 teaches a mobile hydraulic driving machine which comprises: a) a wheeled vehicle having a frame; b) a pedestal mounted on and supported by the frame, having an upright mast; c) a sleeve rotatable on the mast; d) a lower derrick boom pivoted on the upper end of the sleeve; e) an upper derrick boom telescoped in the lower boom; f) a driving tool removably mounted on the end of the upper boom beyond the end of the lower boom; g) a means for rotating the sleeve to position the derrick boom circumferentially of the vehicle; and h) a means for extending and retracting the upper boom to space the driving tool relative to the vehicle. The driving tool has: i) an adjacent upright post with a foot adapted to rest on the ground; ii) a means for controlling the attitude of the post relative to the upper derrick boom; iii) a carriage slidable on the post; iv) a hammer guide mounted on the carriage; v) a spring-loaded anvil depending from the hammer guide; vi) a hammer slidable in the hammer guide adapted to impact against the anvil; vii) a hydraulic lift mechanism for the hammer; viii) tension springs stretched by the lift mechanism for propelling the hammer against the anvil; ix) a dump valve for the mechanism having open and closed cycles; x) a means controlling the rate of the cycles to control the stroke and impact rate of the hammer; and xi) and means for down-crowding the carriage to hold the anvil continuously against the work piece to be driven by the hammer. U.S. Pat. No. 4,869,002 provides an attachment adapted to be mounted to a vehicle for accommodating one of a plurality of tools including a digging bucket, a log splitter, a lifting arm, a post driver or an earth boring auger. The attachment comprises: a) a plurality of horizontal vehicle mounts attached by means of fasteners to the underneath of the front of the vehicle and extending forwardly from the vehicle to form a cradle for receiving a horizontal frame member; b) a horizontal frame member resting in the cradle and held in place by fasteners; c) three sets of swivel devises mounted to the horizontal frame member for receiving a boom swivel or a swing cylinder; d) a boom swivel selectively mounted in any one of the three sets of swivel devises with a swing cylinder mounted in one of the remaining sets; and e) a boom arm having one end pivoted to the boom swivel and adapted to selectively mount one of the plurality of tools. U.S. Pat. No. 4,961,471 sets forth a post hole digger comprising: a) a support base adapted to be mounted on a vehicle for a pivotal movement about a vertical axis; b) a post hole digging auger and motor assembly; c) an elongated support structure pivotally connected at one end to the support base about a horizontal axis. The auger and motor assembly are pivotally connected to the other end of the elongated support structure about a horizontal axis, and the elongated support structure is extendible or retractable to enable positioning of the auger and motor assembly at a desired location and to adjust as the auger and motor assembly lowers and penetrates the ground. The auger and motor assembly are suspended from the elongated support structure so that in a free state the auger and motor assembly is suspended substantially vertically. There is a control handle means present which is adapted to be manually gripped to guide the auger and motor assembly and resist lateral forces occurring during operation of the auger and motor assembly. U.S. Pat. No. 5,746,277 describes an auguring means comprising: a) an extendable mast means having a first mast member and a second mast member, the first mast member having an axis; b) a downcrowding means for extending the second mast member away from the first mast member and for pulling the second mast member towards the first mast member; c) a kelly assembly means having a plurality of telescoping kelly sections which include at least an outer kelly section and an inner kelly section, the outer kelly section having an axis parallel to and spaced apart from the axis of the first mast member; d) a kelly bearing means for rotatably supporting the outer kelly section and for preventing axial displacement of the outer kelly section relative to the kelly bearing means; e) a first support means for supporting the kelly bearing means, and for causing displacement of the outer kelly section along the axis thereof in response to displacement of the second mast member along the axis of, and relative to, the first mast member; f) a kelly rotating means for slidably rotating the outer kelly section about the axis thereof; and g) a second support means for supporting the first mast member and for supporting the kelly rotating means. U.S. Pat. No. 6,155,359 discloses a hole digger system, comprising: a) a spaced apart pair of adjustably extendible support braces, wherein the support braces each have a forwards end; b) an elongate base having a pair of opposite ends, wherein the base is pivotally coupled to the forwards ends of the support braces; c) a telescopic boom arm having a pair of opposite ends and a longitudinal axis extending between the ends of the boom arm, wherein a first of the ends of the boom arm are pivotally coupled to the first of the ends of the base; d) a motor, pivotally coupled to a second of the ends of the boom arm, wherein the motor has a rotating shaft outwardly extending therefrom; e) an elongate auger having opposite mounting and digging ends, wherein the mounting end of the auger are attached to the rotating shaft of the motors. The boom arm has a lowered position wherein the boom arm and the base are extended substantially parallel to one another. The base has a boom rest forwardly extending therefrom, and the boom arm is rested on the boom rest when the boom arm is positioned in the lowered position.
While these devices fulfill their respective, particular objectives and requirements, the aforementioned patents do not disclose a post hole digger that may be fitted to existing vehicles, such as pickup trucks in such a way as to be readily removable from the vehicle for storage, servicing, or placement on another vehicle. In addition, none of the prior art provides a post hole digging apparatus which enables a person owning a pickup truck to add the capability of post hole digging to their vehicle in a matter of seconds. According to the present invention, there is provided such a device, which now means that all which a person needs in order to dig a post hole at any desired location is a pickup truck, a device according to the invention, and a couple minutes of time.
In these respects, the vehicle mounted post hole digger according to the present invention substantially departs from the concepts and designs of the prior art, and provides an apparatus useful for digging post holes in the ground which can be rapidly affixed to any vehicle with a trailer hitch and driven to any desired location to deliver a hole in the ground at a selected location. In addition, a device according to the invention is readily operated by a single person, unlike prior art devices. Thus, two men with two trucks can drastically reduce the amount of time necessary to complete a job task, such as installation of a fence. Finally, the motive energy which a device according to the invention is located on-board of the device, i.e., it has its own source of motive power, as opposed to prior art devices which rely upon PTO's or other motive means.